Her pet had returned home with a chemical burn between its shoulder blades which is thought to have been caused by flea treatment.
Manager of the GSPCA, Steve Byrne, said: “Applying treatments to any animal without following the correct procedures can be more harmful than good. It is important if you feel a cat isn’t owned to try and find its owner before treating it, or at least contact ourselves for advice.
“From allergies to previous treatments and overdosing, applying things such as flea treatments to cats you do not own can be extremely harmful.”

Pictured: Burns like these are caused by a bad reaction to common flea treatments.
The injured cat’s owner said she already treats her pet so she didn’t need any additional flea treatment.
“Yesterday afternoon, my cat came home with a chemical burn in between her shoulder blades where a spot on flea treatment has been applied, said Kirsti Mahieu.
“My cat is treated every four weeks with flea tablets as she reacts to spot on so is not allowed them. This is also overdosing her which can cause kidney failure.”
The GSPCA has a number of bits of advice if you are concerned a cat might be a stray available on its WEBSITE.